Radiocarbon ages: Soil sediment from the Dutch Lake trench was sampled in September 2022. Paleo Research Institute (Golden, Colorado) extracted macrofloral remains (e.g., charcoal) from the sediment samples using liquid separation and sieving and performed charcoal taxonomy. Charcoal samples were submitted to the Woods Hole Oceanographic Institution (WHOI) National Ocean Sciences Accelerator Mass Spectrometry Facility (NOSAMS) and received standard acic-base pretreatment prior to combustion.
Luminescence ages: Sediment from the Dutch Lake trench was extracted for infrared stimulated luminescence (IRSL) dating in September 2022. Chemical and mechanical treatment of sediment was performed to produce aliquots of feldspar. High resolution germanium gamma spectrometry for background dose rate determination, luminescence machine analysis, and age modeling was performed at the U.S. Geological Survey Luminescence Dating Laboratory in Denver, Colorado.
